fix(coding-agent): load tsconfig in source launcher

[FredySandoval]

Summary

• pass the repository tsconfig.json explicitly when running the source launcher through tsx
• document the user-visible fix in the coding-agent changelog

Validation

• npm run check
• launched prime-agent.sh package list from /tmp without building workspace packages

Fixes #904

Note

Fix source launcher to load tsconfig.json when running outside the repository

Adds --tsconfig "$SCRIPT_DIR/tsconfig.json" to the tsx invocation in prime-agent.sh, so the CLI runs correctly even when workspace packages have not been built.

^{Macroscope summarized 5d9cac7.}